Thread cutter for tying machines



Aug. 14, 1945.

E. CUMMINS THREAD CUTTER FOR 'IYING MACHINES Filed June 8, 1944 I N V ENTOR. fl/MM/ms Patented Aug. 14, 1945 Earl Cummins, Kalamazo o ,Mich.ApplicationJune 8, 1944, SerialNo; 539,392

6 cla s. (01. 164-58).

This invention relates to improvements in thread'cutter for tyingmachines.

The main objects of this invention are:

a First, to provide a thread cutter for link'tying machines in which theblade can be quickly removed and re'placed'and at the same time onewhich is eifectively and securely supported.

1 Second, to provide a thread cutter which permits the use offragmentsof safety razor blades or the like as blades. j j Third toprovide a cutter for link tying machines which is well adapted for useinmachines now having considerable use. i

Objects pertaining to details and economies of the invention. willdefinitely appear from the description to follow. The invention isdefined in the claims. i I

l A structure which embodies the features of my invention is clearlyillustrated in the accompanying drawing, in which:

Fig. 1 is a fragmentary view of a link tying machine showndiagrammatically and conventionally having my improved cutter associatedtherewith, only such portions of the machine being illustrated as wouldbe desirable to illustrate a practical application or adaptation of myinvention. I

Fig.12 is a fragmentary plan view illustrating the cutter. partiallyadvanced to the work and as it is about to severthe tying thread "orstrand. Fig.3 is a perspective view of my improved cutter removed fromthe machine, the blade clamp being shown in blade releasing position bydotted lines.

Fig. 4 is a fragmentary view mainly in section on. line 4-4 ofFig. 2.

- Fig. 5 is a perspective view of one of the blades.

. In the operation'of link tying machines used in the manufacture oflink sausages'weiners, and the like, one of the problems is to keepthe'tying strand or thread cutter in suitable condition. While theoperator is expected to keep the blade or cutter to an edge approachingrazor sharpness,

the tendency is to neglect this; with the result that the edge is dulledand fails to cut the thread, the machine becomes clogged, and thematerial being packaged is discharged over and into the machine with ageneral fouling of the apparatus and requiring a shut-down to clean themachine and restore it to operating condition. Further, in such machinesas are now generally in use, considerable time is required to remove andreplace a blade, and this is one reason why the operator of the machineneglects the blades or fails'to give the attention necessar'yfor thesuc'- cessful operation of the machine. I

In the embodiment of my inventionillustrated in the accompanyingdrawing, I, I represent sausage links or weiners, 2 the tyingstrandorthread which is ledfrom'a suitable spool, {not illustrated, throughsuitable guide and tensioning members to the rotary tying head 31 Themachine, designated generally bythe numeral I4, is designed "to feed oradvance the stuffed casings throughthe winding or tying head with astepby step movement. As the details of 'thismecha nism form no part ofmypresent invention I have not illustrated the same hereinlf The cutterarm4 is timed to be actuated'in proper synchronism with the feeding of thestuffed casings and the operation of the winding head. Again, Ihave notillustrated themechanisni forsecuring this timed operation as thatformsno part of my invention.

The knife armis provided with a? bracket 5 carrying a suitable studprovided with a clamping nut 6 for securing my improved blade holder Tto the knife arm. The holder 1 is provided with a laterally openingnotch 8:,to receive the' threaded stud 9 so that the nut fi may beclamped on to the holder fo'rreleasably securing it. The holder isfurther provided with holesllll on either side' of the notch 8 whichengagestuds H on the bracket 5, thereby securelyretaining the bladeholder'ori the arm while permitting 'itsready' removal as occasion mayrequire. The 'holder is provided with a pair of upwardly projectinglaterally spaced studs [2 adapted to engage shoulders]?! formed on theblade I5 by forming opposed notches therein at lGuThes'e notches resultin a shank 0r tang ll disposed between the studs 12 and rearwardlyengaging one of the studs l2. This supports the blade againstrearwardand pivotal tiltingmovement with its cutting edge l8 projectingforwardly beyond theholder and preferably in an inclined relation to thetying thread or strand 2 so as to engage the samewitha draw The bladesl5 may desirably be formed from razor blades such for example asGillette'blades, but in the accompanying drawing I have not attemptedtoillustrate the relative thickness of the blades to other parts or theexact bevel of the cutting edge.

The blade is retained by means of the clamp l9 which is provided with'aclamping arm 2|] extending between the studs l2 and overlapping theblade. The clamp is pivotally and clampingly supported by-means of thecoiled spring 2| which is arranged on the pin 22, the pin being arrangedthrough a hole 23. The inner end of the spring engages the under side ofthe blade holder while its outer end is in thrust engagement with thehead of the screw 24, see Fig. 4. The clamp l9 may be lifted frombetween the studs and swung to position shown by dotted lines in Fig. 3,which releases the blade, and to renew or replace the blade it is onlynecessary to lay it upon the holder with its tang or shank between thestuds and swing the clamp to engaging position. The clamp is supportedagainst pivotal movement when in engaged position by the studs l2 ateach side of the finger portion 20.

With this arrangement I not only provide a blade which has a veryefiective cutting edge, but

" the blades can be replaced or renewed very quickly'and they are veryeconomical. The blades commonly used with this type of machine requirefrequent grinding and the grinding should be done by'askilled workman.As stated, the blades are often neglected and become dull so that thewind'mg strand or thread is not severed. The result isthat the machinebecomes clogged and there is usually a considerable loss of time andmaterial in restoring the machine to operation,

. I have not attempted to illustrate various modifications andadaptations which I contemplate as I have illustrated my invention inahighly "practical embodiment. It is believed that those skilled in theart will be able to adapt my invention as maybe desired, not only forthe specific use in link tying machines but for other uses where highlyeffective thread cuttersare desired. Having thus described my invention,what I claim as new and desire to secure by Letters Patent, is:

1; Ina cutter of the class described, the combination of a blade holdercomprising a plate-like body member having laterally spaced studsthereon, a'flat. blade having an inclined cutting edge superimposed onsaid body, said blade having notchesextending from Opposite edgesthereof receiving said studs and providing a shank extending laterallybehind one of the studs and in thrust engagment therewith to sustaintiltin thrust on said blade, a plate-like clamping member provided withan inclined finger extending between saidstuds in overlapping clampingre- ,lationto said blade, said clamping member havreceiving said studsand providing a shank extendin laterally behind one of the studs and inthrust engagement therewith to sustain tilting thrust on said blade, aplate-like clamping member provided with an inclined finger extendingbetween said studs in overlapping clamping relation'tosaid blade, saidclamping member having a pin thereon disposed through said body member,and a coiled spring arranged on said pin to apply clamping stress tosaid {clamping member.

3. In a cutter of the class described, the combination of a blade holdermember having laterally spaced studs thereon, a flat blade superimposedon said holder member with its cutting edge projecting forwardly beyondth holder member, said blade having. notch-like recesses extending fromopposite edges thereof receiving said studs and providing a shankextending laterally behind one f the studs and in thrust engagementtherewith, a blade clamping member provided with a. finger extendingbetween said studs in overlapping relation to said blade, said bladeclamping member having a pin thereon disposed through said holdermember, and a coiled spring arranged on said pin, said pin beingprovided with a thrust member for the outer end of said spring.

4. The combination in a :cutter of a blade holder member havinglaterally spaced studs thereon, a fiat blade superimposed on said holderbody member with its cutting edge projecting forwardly thereof, saidblade having thrust shoulders in supporting engagement with said studs,and a shank extending between the studs and in rearward engagement withone of them, a blade clamping member provided with a finger extendingbetween th studs in overlapping relation to said blade, said clampingmember having a pin thereon disposed through said holder body member,and a spring associated withsaid pin for applying blade clamping stressto said clamping member, said pin being in longitudinal and pivotalengagement with said holder body member.

5. In a cutter of the class described, the combinationof a flatplate-like holder having laterally spaced studs on the face thereof, aflat blade superimposed on said holder member with its butting-edgeprojecting forwardly beyond the forward edge of the holder member, saidblade having notch-like recesses opening to the front and rear edges ofthe holder member and spaced to receive said front and rear studs withthe edges of the notches in thrust sustaining engagement with the studs,and a blade clamping member pivotally mounted on and resiliently biasedtoward the holder member and provided with a finger extendin between andlaterally supported by said studs in overlapping relation to the bladeand urging it against said holder.

6. In a cutter of the class'descrlbed, the combination of a blade holdermember having laterally spaced upwardly projecting studs thereon, a flatblade superimposed on saidholder'member with its cutting edge projectingforwardly beyond the forward edged the holder member, said blade havingoppositely disposed notch-like recesses in its front and rear edgesproviding a shank disposed and supportingly fitting between said studsand shoulders in thrust engagement with said studs, and a blade clampingmember provided with a finger extending between and I laterallysupported by said studs in overlapping relation to said blade, saidblade holder being resiliently biased to clamp the bladejupon theholder. 1

EARL CUMMIN S.

